RFI - Stormwater Mgm Plan 20169 - SBSMP - Rev 4 (2)

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For maintenance access the shallow nature of the bio-retention systems enables pedestrian
ingress. As noted above no mechanical equipment is required unless resetting is required. The
batter grades are considered to be acceptable and do not pose an occupational health and
safety issue given proper training to maintenance personnel.

The application of pesticides or herbicides in response to any weed outbreak, which cannot be
controlled via manual removal, is to be undertaken by maintenance personnel in accordance
with manufacturer’s guidelines in consultation with the Landscape Architect. Protective
measures are to be implemented so as to minimise exposure to personnel, with personal
protective measures to be the final hierarchical option.


5.8     Public Safety
While maintenance is being undertaken consideration of pedestrians and cyclists is to be made
due to the close proximity of the footpaths. To avoid any safety concerns it is recommended
that temporary warning signs be placed at a sufficient distance to allow pedestrians and cyclists
to become aware of possible maintenance vehicles/personnel when maintenance is being
undertaken.


5.9     Disposal Requirements
The removal of litter and debris, plants, dead or diseased vegetation or weeds are to be
disposed offsite at an appropriate waste management facility.


5.10 Access Issues
Suitable access to the bio-retention basins can be achieved directly from the internal road
network within the site.


5.11 Bio-Retention Basin Resetting
Resetting (i.e. complete reconstruction) of the bio-retention basins will be required if the
system fails to drain adequately after tilling of the surface. Replacement of the filter media is
required when it becomes 50% blocked, which is estimated to occur approximately every 8 to
10 years.

This can be assessed via a review of sediment build up and the time necessary for the system to
drain or by in-situ falling head permeability tests of the filter media.




Bio-Retention Basin Operational Management and Maintenance Guideline